The Note Nobody Read
Everything within normal parameters on both sides.
The term is unexplained infertility, and about a quarter of couples who go through that process get it, and there is no way to convey to somebody who has not had it what that particular sentence does to a marriage.
Because a diagnosis, however brutal, is a fact.
A fact can be planned around.
A fact belongs to a body.
Unexplained belongs to nobody, which means it very quickly comes to belong to whoever the household has already decided is the problem.